The Rev Alan Morris, 63, was free to prey on youngsters at St Ambrose Catholic College, one of Britain's top Catholic schools, over three decades despite repeated attempts by victims to stop him.

Morris, who taught chemistry and religious education, became the highly feared Head of Discipline at the 1,030 pupil school in the wealthy village of Hale Barns, near Altrincham, Cheshire, where he abused boys during break-time for his own sexual pleasure.

Calling himself "the chief policeman" of the school, Morris kept an array of implements in a schoolbag for his punishment beatings and whippings which included the tubing of a Bunsen burner, a cane and a specially adapted table tennis bat known as "the paddywhacker".

“The devout Catholic parents felt staff could do no wrong. It was a shocking abuse of trust and incredibly arrogant behaviour”

Judge Timothy Mort

Boys would be routinely targeted during lessons and were spanked, sometimes in front of other pupils and often in the storeroom of Morris' chemistry laboratory, for misdemeanours including low marks in tests, running along a corridor and making too much noise.

At Minshull Street Crown Court, Morris was convicted of 17 indecency charges on ten former pupils aged between 11 and 17 during their time at the school following two trials.

He was originally charged with offences involving 29 former pupils but various charges will be allowed to lie on file. His convictions can only be reported now as his previous trials were heard in secret for legal reasons.

One boy tried to complain about Morris as long ago as 1973 but the then headmaster of the independent school which was run by an Irish Christian Brothers Holy Order ignored his claims and shouted at him instead.

IGNORED: Victims who came forward about abuse were either ignored or told to keep quiet [CAVENDISH]

Another who tried to report Morris to police in 1986 was pressurised by parents to drop his complaints for fear his claims would scandalise the local Catholic community.

Police were eventually called in to investigate Morris in 2001 after his retirement when another former pupil came forward — but despite arresting and quizzing him, no further action was taken after he insisted he had taken a vow of celibacy.

Morris' 23-year reign of terror finally caught up him when a fourth ex-pupil went to police in 2012 — the ensuing publicity about the investigation triggering a huge influx of victims who had previously suffered in silence.

Morris kept his eyes shut and clutched his walking stick in the dock as Judge Timothy Mort told him: "It was clear you administered corporal punishment regularly and enthusiastically.

"One can sympathise that discipline is important but against that philosophy you regularly administered punishment. It then became clear that you had an unhealthy interest in pupils' bottoms.

"Mostly, the devout Catholic parents felt staff could do no wrong. It was a shocking abuse of trust and incredibly arrogant behaviour."